The present invention relates to a load carrier strut which is designed to be secured, with at least one end portion, in a load carrier foot which is fixable on a vehicle roof, the load carrier strut having a hollow profile, being exteriorly provided with an enveloping protective skin of plastic, rubber or similar material, and having at least one longitudinal slot through which extend means for securing the load carrier strut to the load carrier foot, or for securing a load or load carrying device on the load carrier strut.
The present invention also relates to a method of manufacturing a load carrier strut which is designed to be secured, with at least one end portion, in a load carrier foot which is fixable on a vehicle, the load carrier strut being given hollow profile, being exteriorly provided with an enveloping protective skin of plastic, rubber or similar material, and at least one longitudinal slot.
Load carrier struts of the type disclosed by way of introduction are previously known in the art. Normally, these load carrier struts have an interior of metal which is produced from hollow profiles whose cross section may be rectangular, circular or substantially oval. Most generally, the load carrier strut is provided on its underside and along its opposing end portions with longitudinal slots which are employed for the insertion of a suitable clamping device on a load carrier foot, so that this may be clamped in place on the load carrier strut at any optional position along the length of the slot.
It may also occur that the load carrier foot and load carrier strut are joined together in a different manner but that the load carrier strut has one or more longitudinal slots or undercut grooves for securing a load or a load-carrying device.
In order to protect the load carrier strut from corrosion, and the load borne by the load carrier strut from damage, it is normal that the load carrier strut be provided with an external, protective skin or coating of plastic, rubber or similar material. Normally, this protective skin is extruded about the load carrier strut so as to form a sheath or envelope about the strut. Adhesion between this envelope and the subjacent metal material may be defective, but as long as the envelope or protective skin is undamaged and displays no longitudinal breaches of any appreciable length, this circumstance is of minor importance.
When longitudinal slots are made in a load carrier strut provided with a protective skin in this manner, those portions of the protective skin that are located around the slot will have no adhesion to the substrate, for which reason these parts of the protective skin may readily be damaged, deformed or otherwise destroyed. Further, the surfaces which define the slot are freely exposed to corrosion.
Problem Structure
The present invention has for its object to realize a load carrier strut of the type disclosed by way of introduction, the load carrier strut being designed in such a manner that the drawbacks inherent in prior art versions are obviated. In particular, the present invention has for its object to realize a load carrier strut in which the protective skin lodges securely in place despite the presence of a longitudinal slot and in which the surfaces on the load carrier strut defining the slot are protected against corrosion.
The present invention further has for its object to realize a load carrier strut which is simple and economical to manufacture.
The present invention still further has for its object to realise a method of the type disclosed by way of introduction, the method permitting the manufacture of a load carrier strut in which the resulting protective skin is held in place on either side of the longitudinal slot and in which the surfaces on the load carrier strut proper which define the slot are protected against corrosion.
Solution
The objects forming the basis of the present invention will be attained in respect of the load carrier strut, if this is characterized in that the protective skin is disposed to cover at least the major portion of those surfaces on the load carrier strut which define the slot therein.
The objects forming the basis of the present invention will be attained in respect of the method, if this is characterized in that the slot is made in the load carrier strut before this is provided with the protective skin, that this skin is applied to the load carrier strut in sheath-like formation and also covering the slot, that a recess is formed in the portion of the protective skin covering the slot, the recess being made smaller than the slot so that the protective skin is given a projecting portion which extends somewhat outside that edge which defines the slot, and that the projecting portion is formed so as to cover at least the major portion of the surfaces on the load carrier strut defining the slots.